Bug #71375 [Nab]: Memory not released from token_get_all()

Edit report at https://bugs.php.net/bug.php?id=71375&edit=1 ID: 71375 User updated by: pete at peteward dot net Reported by: pete at peteward dot net Summary: Memory not released from token_get_all() Status: Not a bug Type: Bug Package: Performance problem Operating System: Centos Linux 7.0 PHP Version: 7.0.2 Block user comment: N Private report: N New Comment: Thank you! Previous Comments: ------------------------------------------------------------------------ [2016-01-15 04:40:32] bwoebi@php.net This isn't a bug, but a side effect of the new memory manager which caches more memory and doesn't release memory back to the OS so quickly. Try setting the first parameter of memory_get_usage to false. You'll then see the memory PHP really needs. Also, try calling gc_mem_caches() first before measuring. This releases unused memory segments. This is intentional behavior, though it is possible that this gets quite extreme in cases like token_get_all(). See also bug #70098 ------------------------------------------------------------------------ [2016-01-14 22:11:39] pete at peteward dot net Description: ------------ Memory leaked from token_get_all() is much worse in php 7.x than in 5.x. I have a large Symfony app with a container file string which when passed through token_get_all() hangs on to a large amount of it's consumed memory, despite the peak consumption being less. I haven't managed to identify which tokens are causing this as a basic very large string didn't have this issue, however the test script below shows how it works with the 'real' content (a symfony container). Test script: --------------- <?php printMemory(); $string = file_get_contents('http://dev.radiancedaily.com/appDevDebugProjectContainer.txt'); printMemory(); getAllTokensInScope($string); printMemory(); function printMemory() { $mem = str_pad(round((memory_get_usage(true)/1024/1024)), 3, " ", STR_PAD_LEFT) . "MB " . str_pad(round((memory_get_peak_usage(true)/1024/1024)), 3, " ", STR_PAD_LEFT) . "MB "; print $mem . PHP_EOL; } function getAllTokensInScope($string) { $something = token_get_all($string); } Expected result: ---------------- Memory should be released outside of the scope of the function from which it's called. PHP 5.4 and 5.6: $ php -v PHP 5.6.14-0+deb8u1 (cli) (built: Oct 4 2015 16:13:10) Copyright (c) 1997-2015 The PHP Group $ php test.php 0MB 0MB 3MB 3MB 11MB 210MB Actual result: -------------- Most of the memory is not released. $ php -v PHP 7.0.2 (cli) (built: Jan 9 2016 14:00:11) ( NTS ) Copyright (c) 1997-2015 The PHP Group $ php test.php 2MB 2MB 7MB 7MB 111MB 130MB ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=71375&edit=1